Okay, an update. I disconnected the DVD as it is SATA and may be conflicting with the new SATA HD. The new HD is still not recognized, and even after I ran the program "Fresh Diagnose", which shows about everything on the computer, the new HD is STILL not recognized!
However, when I check with the device manager, it shows the HD, and says the SCSI device is working properly. How's can that be, as the unit doesn't show up when I access "Explore" and see what's on the computer?
I've even tried to update drivers, thinking it needed something more than it has, but the message comes back that the driver is current.
Now I'm confused!